This document discusses two main types of digital images: vector and bitmap. Vector images are resolution independent and can be scaled without quality loss since they are constructed through mathematical expressions. Bitmap images have finite resolution and pixel dimensions, so scaling them can result in quality degradation. The document also covers factors that impact image quality like compression and resolution. It describes common file formats, programs, and uses for each image type as well as methods for image capture, output, storage, and asset management.

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UNIT 13 – ASSIGNMENT 1
DIGITAL IMAGES: two kinds of images
1. Vector
2. 2. Bitmap (Raster)
VECTOR
- Made of points, lines and curves – the image is built and displayed through
mathematical expressions.
- It can be scaled (re-sized) and will not lose clarity or quality.
- Resolution - independent – can be – printed at any resolution.
Common file formats: .ai, .cdr, .ps, .pds
Common vector graphic programmes: Adobe illustrator, CorelDraw, FreeHand
Common uses of vector graphics: Drawing, illustrations, cartoons
BITMAP (RASTER)
-made up of pixels
- Resolution – dependant – it can be scaled up without losing quality.
Common bitmap files: .jp, .jpeg, .gif, .png, .tif, .tff, .bmp
Common bitmap images: Photographs and paintings.
PIXEL
-The smallest part of a bitmap (raster) image. This pixel will havea single colour. If
you zoom in far enough, or scale a bitmap image up, you can see its pixels.
Or

2. RAGWANA AKRAM
-The smallest controlled element of a screen. Each pixel on a screen emits Red,
Green and Blue light. By changing the levels of each colour (Red, Green, Blue) your
screen is able to produce every possible colour.
FACTORS WHICH IMPACT IMAGE QUALITY
-Compression: this is when you try and reduce the size of the file, perhaps to make it
easier to send to someone else.
-By compressing the image you lose data, this means you lose quality.
Resolution: This is the size of an image. It is how many pixels tall, wide, an image is
The higher the resolution = the better the quality, however this means the file is
larger. Resolution only applies to bitmap images.
IMAGE CAPTURING
1. Scanning an image which has been drawn. This image cannot be resized
without losing quality.
2. Digitally drawing an image in Photoshop with a sketchpad and stylus. This
image can be resized, providing it is being drawn as a vector image.
3. Using a digital camera. Simply takes a photo which is saved digitally. Stored
as a bitmap image, so it will lose quality if re-sized.
OUTPUT
How an image will be outputted often determines the kind of an image it needs
to be.
Outputs: print (paper), screen & online.
Print: printing uses the CYMK pallet (Cyan, Yellow, Magenta, and Black)
Screen: use pixels to display and image, so uses the RGB colour pallet (Red,
Green, Blue)
STORAGE
File size: The larger an image is, or the higher its resolution, the larger the file is:
- Harder to email
- Longer to download
- Takes up more space in a computer’s memory
Naming conventions: It is important to save work with suitable names so you, or
others, can locate them. If you are working on a large project as part of your
team your files must be organised and named appropriately.
Asset management: when working on a project , or any work, it is important to
keep files organised.

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- Save work, with suitable names, into correct folders.
- This means others are able to use and access your work, and you are able to
access theirs efficiently.